Manhole covers are known to be usually made of cast iron and often times they are of substantial size and weight and they are difficult to handle. Manhole covers are used to cover manholes which lead from street level down to a sewer or other utility device. Usually such manhole covers are very firmly seated in their seats at ground level or at the level of the roadway so that the manhole cover will not wobble and make noise when a vehicle drives over it. Often times some additional sealing material such as tar will be used in sealing the manhole cover in its desired location.
Accordingly, manhole covers are extremely difficult to lift in many instances and even where the manhole cover is reasonably loose in its seat, the manhole cover is certainly an object of substantial weight and odd dimensions as to make it difficult to lift and handle.
In the past, it has been common practice to lift a manhole cover slightly with a pick ax, and after the manhole cover has been lifted slightly and tilted up, the edge of the manhole cover is manually grasped and the cover is lifted additionally and then rolled out of the way. Of course, after the manhole cover has been rolled off to the side, it must be lowered to the ground or pavement again, and in order to prevent breaking the cast iron, the manhole cover must be actually lowered to the ground instead of allowed to simply fall over.
In using a pick ax, there is generally found a hole in the center of the circular manhole cover which will accommodate the point of a pick ax. The point of the pick ax will be inserted into the hole at the center of the manhole cover and then the ax handle will be lifted manually so as to tip the manhole cover upwardly and outwardly of its seat. Because of the difficulty in lifting manhole covers and in loosening them and moving them out of the way, workmen have experienced an unusual number of back injuries in doing this work. Also there is a propensity to injure the workman's hands or fingers as the manhole cover is handled, and especially as the manhole cover is laid down on the pavement next to the opening or as the manhole cover is replaced onto its seat in the opening.